Spark gap



Dec. 2, 19274.

R. H.4 MARRIOTT SPARK GAP Filed Nov. 1l

Mirar-ne] Patented Dec. 2, i924,

ROBERT H. MARRIOTT. QF BREMERTO'N, WASHINGTON.

SPARK GAP.

To a-ZZ whom t may concern:

Be it known that I, ROBERT H. MARRIOTT, a citizen of the United States of America, residing at Bremerton, in the county of Kitsap, State of Washington, have invented certain new and useful Improvements in Spark Gaps, of which the following is a specification.

My invention relates generally to spark gaps and more particularly to quenched spark gaps for radio transmission, and has for an object the provision of a means to prevent the leakage of gas from the spark chamber and the consequent admission of air thereto.

Another object of the invention is to provide an auxiliary chamber for the reception of the expanded gas and vapors incident to the spark.

With these and other objects in view the invention consists in the construction, combination and arrangement of parts as will be hereinafter described.

Reference is to be had to the accompanying drawings, forming part of this specification, in which like reference characters indicate corresponding parts throughout the several views, and in which:

Figure l is an elevation of my invention, and

Figure 2 is a sectional view of the same.

' The preferred embodiment of my invention consists of the circular metal plates 1. and 2 having sparking surfaces 3 and 4 respectively which are separated and insu lated by a suitable gasket 5 of mica or other insulating material, forming the spark chamber or gap 6. These plates may be clamped together by any suitable method practiced in the art.

In assembling quenched spark gaps of the common type more or less air is confined in the chamber which apparently it is necessary to convert by electric current into gas of another form before successful spark regularity and quenching is obtained. This new gas expands when the gap is in use and under the increased pressure leaks out around the insulating gasket permitting,

Application filed November l, 1921. Seria No. 512,059,

when cooling takes place and a partial vac- '30 uum exists, additional air to enter the chamber, which new air oxidizes the sparking surfaces increasing their resistance to the detriment of the device. When the spark gap breaks down, the gap is filled with metallic i5 vapor, and if this vapor, which produces the conductivity of the spark, is not removed from the gap the insulation will be poor, materially decreasing the spark eiciency.

To permit the expansion of gas without 5U its escape and consequent admission of new air into the chamber, and the diifusion of metallic vapor without the necessity of air blast or other forms of forced removal, I

have constructed a flexible chamber 7 having the end 8 sealed and the open end embedded in any suitable manner in the plate l as at 9, the chamber being so constructed that its volume will vary with the pressure of the enclosed gas. The open end of the chamber has communication with the spark chamber 6 through a passage-way 10, permitting the entrance of gas or vapors from the spark chamber into the iiexible chamber.

It is to be understood that the above description and the accompanying drawings comprehend only the general and preferred embodiment of my invention and that minor changes in construction, proportion and arrangement of parts may be resorted to within the scope of the appended claims and without sacriiicing any of the advantages of my invention.

Having fully described my invention what I claim as new'is:

1.- A spark gap having a spark chamber and a pressure relief chamber having eX- pandible walls communicating therewith,

2. A spark gap comprising a plurality of plates spaced apart by an insulated gasket 90 forming a spark chamber therebetween, and a tubular member having one end closed and expandible walls and having its open end embedded in one of said plates, said member having communication with said chamber 9E through a passageway therebetween.

i ROBERT H. MARRIOTT. 

